The composition according to the invention is suitable in particular for rolling, dishing, drawing, pressing of metals in general of the iron and non-iron type such as steel, copper, aluminum, and alloys thereof.
The use of liquids acting as lubricants in the above metal processing processes is well known. The liquids, which generally consist of hydrocarbon oils with various additives for improving the performances thereof under severe operative conditions (high pressures, high temperatures), exhibit the drawback of being inflammable.
In latest times, the use of aqueous emulsions comprising matters endowed with lubricating properties has been suggested. Such products, besides being practically not affected by the drawback of being inflammable under the operating conditions, satisfactorily fulfill also the task of cooling the materials under processing. Lubricating compositions of this type are described, for example, in European Patent No. 48,216 (Alusuisse), Canadian Patent No. 987,655 (Exxon), U.S. Pat. No. 4,585,565 (Alcoa), and U.S. Pat. No. 4,618,441 (Alcoa), all hereby incorporated by reference. Although many compositions in the form of aqueous emulsions have been suggested, it should be understood that it is very difficult to prepare a composition which exhibits excellent performances regarding lubrication and cooling, a low friction coefficient (to achieve high reduction ratios). Furthermore, the composition should be endowed with good lubricating properties at high pressure. At the same time, the composition should be free from various drawbacks such as instability of the emulsion which can undergo a demixing under operating conditions.
The known compositions always require specific additives depending on the fields of use, to reach good values of the specific properties which are of major interest for the expected use.